Upload progress bar now displays informations about uploads...

Upload progress bar now displays informations about uploads, uploades size (e.g. 12kB of 3MB) and the current speed.

Making this PR for this: #8105 

Here is a live test:
user: test
pw: bla
http://flutterb.at/owncloud-testserver

should replace https://github.com/owncloud/core/pull/10324
@bantu then please test it?